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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
911

An assessment of indoor and outdoor air quality in a university environment : a case of University of Limpopo, South Africa

Mundackal, Antony Jino 23 June 2021 (has links)
Air pollution of late has been the focus of many studies due to the detrimental health risks that it poses to individuals. University environments have several academic departments with peculiar activities that could be affecting the indoor and outdoor air quality (AQ) of these environments. University settings differ from other environments because of the variety of activities and different lines of work that go on inside buildings housing academic departments and their surroundings, which are likely to have an impact on indoor air quality (IAQ) and outdoor air quality (OAQ) in this environment. Only a few AQ studies have been done in university sites and surrounds worldwide and in these studies, IAQ was given primary importance; whereas, the outdoor environment was and is often neglected. A study comparing both IAQ and OAQ is critical to further understand the relationship between IAQ and OAQ within a university campus. The University of Limpopo (UL) in the Mankweng township of South Africa has been undergoing some refurbishments with numerous construction activities going on in addition to the academic activities of UL. These activities may be affecting the AQ in this unique environment. The main aim of this study was to determine differences between indoor and outdoor AQ in a university environment and to understand how AQ in this unique environment varies with seasons and building function. The study was carried out in three buildings housing three different academic departments in UL namely: Department of Physiology and Environmental Health (PEH), Department of Biochemistry, Microbiology, and Biotechnology (BMBT) and the Department of Biodiversity (BIOD). Twenty indoor and 20 outdoor measuring sites were identified per departmental building from where real-time measurements of 11 AQ parameters (linear air velocity (LAV), dry-bulb temperature (Tdb), relative humidity (RH), carbon monoxide (CO), carbon dioxide (CO2), ozone (O3), sulphur dioxide (SO2), nitrogen dioxide (NO2), hydrogen sulphide (H2S), non-methane hydrocarbons (NMHCs) and volatile organic compounds (VOCs)) were taken over three consecutive days per season. Thus, a total of 60 indoor and 60 outdoor measurements were taken for each parameter in each of the three buildings of interest per season, leading to 360 measurements per season and 1440 measurement per parameter over the one-year period of study across the study area. A hot-wire anemometer was used to measure LAV, whereas the Q-Trak indoor AQ monitor was used in the measurement of Tdb, RH, CO and CO2. Aeroqual AQ monitors were employed in the measurement of O3, SO2, NO2, H2S, NMHCs and VOCs. The Wilcoxon signed ranks test was used to determine differences between indoor and outdoor environments. Significant differences were found between the indoor and outdoor environments for LAV (all three buildings), Tdb (PEH and BMBT), RH (BIOD), O3 (all three buildings), NO2 (all three buildings), CO (all three buildings), CO2 (all three buildings), NMHCs (BMBT and BIOD), and VOCs (all three buildings) (p < 0.05). Linear air velocity, O3, SO2, CO, CO2, and H2S values/concentrations across the indoor/outdoor environments were within the ASHRAE/DEA/WHO guidelines/standards, whereas Tdb, RH and NO2 values/concentrations were not. Air quality in the study area varied with building, with the best AQ across both the indoor and outdoor environments being within the BIOD building, whilst the worst AQ across both environments was encountered in the PEH building. Seasonal differences between buildings were also identified between indoor and outdoor environments among the PEH, BMBT and BIOD buildings (p < 0.008). Across the indoor environment, the winter season was found to be the season with the best AQ, since all the pollutants were found at minimum concentrations. Factors affecting AQ in the study area included thermal comfort, occupant densities, building function, laboratory emissions, renovation activities, generators, vehicular emissions, among others. The best AQ across the outdoor environment occurred during the autumn season, since all the air pollutants were present at minimal concentrations during this time. The best predictors of LAV, Tdb, CO, CO2, NO2, and NMHCs were seasons (R2 = 1.000, p < 0.01). For the parameters RH, H2S, and VOCs, the best predictor was building type (R2 = 1.000, p < 0.01). The indoor and outdoor environment were the best predictors for SO2 (R2 = 0.999, p < 0.01). Ozone had no single predictor that was found to significantly influence its concentration in this study. In relation to an air pollution index (API), generally all pollutant indices fell within the fair, good to very good range when using mean and maxima concentrations, whereas, corresponding NO2 concentrations throughout the study fell within the poor to very poor range (105.660–250.000). University management should take into consideration ventilation in laboratories, occupant densities and location of standby generators and car parks in the management of AQ on the university campus. All heating, ventilation and air conditioning (HVAC) systems need to be upgraded and work in tandem with natural ventilation when having high occupant densities within buildings. Future studies in this sector could incorporate larger sample sizes, be designed as a longitudinal study, and make use of questionnaires and sample more AQ parameters to get a detailed understanding of a university site and its surrounds. / Environmental Sciences / Ph. D. (Environmental Science)
912

Evaluation of Indoor Air Quality in Four Nursing Home Facilities in Northwest Ohio

Tebbe, Hope M. 18 October 2017 (has links)
No description available.
913

A review of the control of motor vehicle fuel specifications and its effects on air quality

Choi, Ya-yin., 蔡雅然. January 2003 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
914

Air quality modeling : evaluation of chemical and meteorological parameterizations / Modélisation de la qualité de l’air : évaluation des paramétrisations chimiques et météorologiques

Kim, Youngseob 15 December 2011 (has links)
L'influence des paramétrisations chimiques et météorologiques sur les concentrations de polluants calculées avec un modèle de qualité de l'air est étudiée. L'influence des différences entre deux mécanismes chimiques de la phase gazeuse sur la formation d'ozone et d'aérosols en Europe est faible en moyenne. Pour l'ozone, les fortes différences observées localement proviennent principalement de l'incertitude associée à la cinétique des réactions d'oxydation du monoxyde d'azote (NO) d'une part et de la représentation des différents chemins d'oxydation des composés aromatiques d'autre part. Les concentrations d'aérosols sont surtout influencées par la prise en compte des précurseurs majeurs d'aérosols secondaires et le traitement explicite des régimes chimiques correspondant au niveau d'oxydes d'azote (NOx). L'influence des paramétrisations météorologiques sur les concentrations d'aérosols et leur répartition verticale est évaluée sur l'Île de France par comparaison à des données lidar. L'influence de la paramétrisation de la dynamique de la couche limite atmosphérique est importante ; cependant, c'est l'utilisation d'un modèle de canopée urbaine qui permet d'améliorer considérablement la modélisation de la répartition verticale des polluants / The influence of chemical mechanisms and meteorological parameterizations on pollutant concentrations calculated with an air quality model is studied. The influence of the differences between two gas-phase chemical mechanisms on the formation of ozone and aerosols in Europe is low on average. For ozone, the large local differences are mainly due to the uncertainty associated with the kinetics of nitrogen monoxide (NO) oxidation reactions on the one hand and the representation of different pathways for the oxidation of aromatic compounds on the other hand. The aerosol concentrations are mainly influenced by the selection of all major precursors of secondary aerosols and the explicit treatment of chemical regimes corresponding to the nitrogen oxides (NOx) levels. The influence of the meteorological parameterizations on the concentrations of aerosols and their vertical distribution is evaluated over the Paris region in France by comparison to lidar data. The influence of the parameterization of the dynamics in the atmospheric boundary layer is important ; however, it is the use of an urban canopy model that improves significantly the modeling of the pollutant vertical distribution
915

Análise de metodologias de determinação da viabilidade de implantação de tecnologias, técnicas e práticas, para gerenciamento de emissões de material particulado, na Região Metropolitana de São Paulo / Analysis of methodologies for determining the feasibility of implementing technologies, techniques and practices for the particulate matter management of emissions in the Metropolitan Region of São Paulo

Rocha, Priscila Freire 19 June 2019 (has links)
A gestão da qualidade do ar é um desafio global, considerando que em muitos países, como no Brasil, a concentração da população em regiões metropolitanas é relevante, assim como sua exposição à poluentes atmosféricos. No estado de São Paulo, ao longo dos anos, as regulações que integraram a gestão da qualidade do ar têm incorporado novos instrumentos, exigências. Porém, identifica-se a ausência de procedimentos oficiais para auxiliar a concepção de políticas públicas. O objetivo deste trabalho foi de analisar metodologias existentes nos Estados Unidos da América e União Europeia, que possam auxiliar o planejamento de políticas públicas de qualidade do ar, em especial, para material particulado na Região Metropolitana de São Paulo (RMSP) e também de análises de viabilidade técnica e econômica de implantação de novas tecnologias, técnicas e práticas, do inglês Best Available Techniques (BAT)/ Best Environmental Practices (BEP). Por meio de pesquisa exploratória, utilizando-se de revisão bibliográfica e documental, este trabalho verificou a ausência sistemática de elementos como: análises de custo-efetividade de políticas públicas, consideração de modelagens integradas para concepção de políticas públicas, envolvimento de partes interessadas no planejamento de medidas. Quanto aos elementos para realizar análise de viabilidade técnica de implementação de BAT/BEP, foi possível identificar aspectos de avaliação de efeitos cruzados ambientais e econômicos, bancos de dados americanos e europeus contendo BAT/BEP e seus custos, que, com a devida adaptação, poderiam ser também uma referência. Trata-se de elementos importantes para subsidiar tomadas de decisão e buscar medidas, para que possam, de fato, levar à melhoria da qualidade do ar, para material particulado (MP10). / Air quality management is a global challenge, considering that in many countries, such as Brazil, the concentration of population in metropolitan regions is relevant and also their exposure to air pollutants. In the state of São Paulo, over the years, regulations that have integrated air quality management have incorporated new instruments, requirements. However, it is identified the absence of official procedures to assist the design of public policies. The objective of this work was to analyze existing methodologies in the United States and the European Union, which can assist in the planning of air quality public policies, especially for particulate matter in the Metropolitan Region of São Paulo (RMSP), as well as technical and economic feasibility analyzes for implementation of new technologies, techniques and practices from Best Available Techniques (BAT) / Best Environmental Practices (BEP). Through an exploratory research, using a bibliographical and documentary review, this work verified the systematic absence of elements such as: cost-effectiveness analysis of public policies, consideration of integrated modeling for public policy design, stakeholder involvement in planning of measures. As for the elements to perform technical feasibility analysis of BAT / BEP implementation, it was possible to identify aspects of environmental and economic cross-effects evaluation, American and European databases containing BAT / BEP and their costs, which, with due adaptation, could also be a reference. Those are important elements to support decision-making and seek measures, so that they can, in fact, lead to improved air quality for particulate matter (PM10).
916

Modélisation numérique de la couche limite atmosphérique par condition stable en terrain complexe. Application à la qualité de l'air / Numerical modelling of the stable atmospheric boundary layer over complex terrain and application to air quality

Quimbayo-Duarte, Julian 13 March 2019 (has links)
En hiver, par condition anticyclonique hivernale, les régions montagneuses urbanisées font l'objet de conditions atmosphériques stables et découplées, qui conduisent à des épisodes de forte pollution particulaire. Ce travail de thèse traite de la caractérisation des facteurs de pollution de l'air aux particules par condition stable en vallée alpine encaissée, du point de vue de la dynamique atmosphérique. Ce travail repose sur des simulations numériques idéalisées et en conditions réelles à l'aide du modèle Weather Research and Forecasting (WRF), les particules étant modélisées par un champ de traceur passif.Dans une première partie, des simulations numériques à haute résolution ont été réalisées, en utilisant deux configurations différentes de vallées tridimensionnelles idéalisées ouvrant sur une plaine. La première configuration correspond à une vallée de largeur constante dans la direction de l'axe de la vallée ouvrant sur une plaine. Dans la seconde configuration, la vallée est composée de deux sections, la section aval, qui ouvre sur la plaine, étant plus étroite que la section amont. Cette configuration est appelée "pooling". Quelle que soit la configuration, la variation du profil vertical de température le long de l'axe de la vallée conduit à d'un gradient de pression horizontal générant un vent de vallée. Les configurations de type "pooling" sont associées à des concentrations de polluants plus élevées que dans le cas où la largeur de la vallée ne varie pas, car le vent de vallée est plus faible dans la configuration "pooling". L'impact de la largeur de la section aval sur la concentration de polluants dans la section amont est remarquable: la ventilation de la section amont peut être complètement bloquée pendant la majeure partie de la simulation (six heures) lorsque le rapport de largeur de la section amont à la section aval est égal à 10.La deuxième partie concerne une situation réelle en vallée alpine, durant un épisode fortement pollué de février 2015. La dynamique atmosphérique et la concentration de particules fines (PM) ont été modélisées dans une section de la vallée de l'Arve autour de la ville de Passy par le modèle WRF-Chem durant cet épisode. Pour cela, le cadastre d'émission préparé par l'agence de qualité de l'air de la région Auvergne Rhône-Alpes a été implémenté dans le modèle. La dynamique de la couche limite a été comparée à des profils verticaux de vent et température mesurés lors d'une campagne de terrain durant l'épisode pollué, et la concentration de PM comparée aux données de stations de qualité de l'air. La contribution des vallées tributaires à la pollution atmosphérique dans cette section de la vallée de l'Arve a d'abord été étudiée. Les résultats montrent que cette contribution est très faible par rapport à celle des sources locales; ceci implique que les émissions $in-situ$ sont principalement responsables de la forte concentration de particules polluantes enregistrée dans la vallée car le fond de vallée est découplé de l'atmosphère au-dessus de la vallée. Les processus de ventilation et leur influence sur la concentration de particules (PM) ont ensuite été étudiés. L'analyse montre qu'en raison de la ventilation limitée autour de la ville de Passy, la variabilité horaire de la concentration de PM dans la ville est contrôlée par les émissions. / During wintertime anticyclonic regimes, urbanized mountain areas often experience stable and decoupled atmospheric conditions, resulting in severe episodes of particulate air pollution. This study deals with the characterization of drivers of particulate air pollution in deep alpine valleys under such stable conditions from the point of view of atmospheric dynamics. The work has been carried out through the implementation of both idealized and real case numerical simulations using the Weather Research and Forecasting (WRF) model. Particulate air pollution has been modelled by implementing passive tracers in the simulations.In a first part, high-resolution numerical simulations have been performed using two different configurations of three-dimensional idealized valleys opening onto a plain. The first configuration corresponds to a valley of constant width in the along-valley direction, directly opening onto a plain. The second one consists in a valley of varying width in that direction, with an upstream section of larger width than the downstream section, which opens onto the plain. The latter configuration is referred to as a pooling case. The change in the vertical temperature profile along the valley axis in all configurations results in a horizontal pressure gradient that leads to the development of an along-valley flow. Configurations in which the upstream section of the valley opens onto a narrower one have shown to be prone to higher pollutant concentrations than in the case of a valley opening directly onto a plain, due to the weaker down-valley flow developing in the variable width configurations. The impact of the downstream valley section on the concentration of pollutants in the upstream valley section is remarkable: the ventilation of the upstream valley section can be completely blocked for most of the simulation (six hours) when the ratio of the upstream to downstream valley section width is equal to 10.The second part deals with a real case situation, focusing on a section of the alpine Arve River valley around the city of Passy. The numerical modelling of the atmospheric dynamics and particulate matter (PM) concentration in that section has been performed during a strongly polluted wintertime episode of February 2015. For this purpose the emission inventory prepared by the air quality agency of the région Auvergne Rhône-Alpes has been implemented in the WRF-Chem model. The boundary layer dynamics has been compared to wind and temperature profiles collected during a field campaign conducted during the episode, and PM concentration has been compared to data recorded by air quality stations. The contribution of the valley tributaries to air pollution within the section considered has been first studied. Results show that this contribution is very small compared to that from local sources; this implies that $in-situ$ emissions are primarily responsible for the high PM concentration recorded in the valley since the valley bottom is decoupled from the atmosphere above the valley. The ventilation characteristics of the valley and their influence on the particulate matter (PM) concentration have next been investigated. The analysis indicates that due to the limited ventilation around the city of Passy, the hourly variability of PM concentration therein is driven by that of the emissions.
917

Avaliação da qualidade ambiental interior de um edifício climatizado artificialmente com ênfase na análise do conforto térmico / Evaluation of indoor environmental quality of an artificially conditioned building, focusing on thermal comfort analysis

Silva, Ana Flávia Silveira 25 November 2010 (has links)
Ocupantes de ambientes internos climatizados artificialmente estão expostos contínua e prolongadamente a condições ambientais muitas vezes desfavoráveis à execução de suas atividades e à manutenção da saúde. O objetivo desta pesquisa foi avaliar alguns parâmetros de qualidade do ar interior e de conforto térmico de um edifício climatizado artificialmente e relacioná-los à utilização de sistema de condicionamento de ar com distribuição pelo piso em ambientes que não são caracterizados como escritórios abertos. Considerando que o edifício estudado apresenta usos distintos de seus pavimentos, optou-se pela avaliação de dois deles, um pavimento cujo layout é de salas de aula e outro de escritório semi-aberto. Os parâmetros foram analisados em três momentos distintos. O primeiro se caracteriza por três ciclos semestrais de medições de temperatura, umidade relativa e velocidade do ar, concentração de aerossóis, dióxido de carbono e fungos. A segunda etapa consiste em uma campanha única de medições, com duração de quatro dias, permitindo a realização de perfis de temperatura e umidade relativa, avaliação das velocidades do ar em pontos de desconforto e cálculo dos índices de conforto térmico PMV (Predicted Mean Vote) e PPD (Predicted Percentage of Dissatisfied). Em um terceiro e último momento, aplicou-se o questionário de qualidade ambiental interior aos ocupantes de ambos os pavimentos. Resultados obtidos nos ciclos permitiram identificar concentrações de fungos e dióxido de carbono acima dos limites indicados. Os perfis de temperatura revelaram a predominância das mesmas abaixo do recomendado. O cálculo dos índices PMV e PPD apontaram para um cenário de maior conforto térmico nos ambientes estudados com temperatura operativa igual a 24 graus Celsius. Os resultados dos questionários corroboraram as medições de temperatura, indicando a prevalência das sensações térmicas relacionadas ao frio entre os ocupantes do edifício, em especial aqueles do sexo feminino. Ficou evidenciado que o conforto térmico nos ambientes pesquisados é um fator perturbador das atividades exercidas em ambos os pavimentos. Houve um grande número de relatos de ocupantes com sintomas típicos da Síndrome dos Edifícios Doentes (SED), sugerindo que medidas relativas à qualidade ambiental devem ser tomadas em prol da saúde, bem estar e produtividade dos ocupantes do edifício. Concluiu-se que a operação e manutenção do sistema de condicionamento de ar com insuflamento pelo piso em ambientes distintos de escritórios abertos são mais complexas e, por isso, dificultam o alcance de uma qualidade ambiental interior satisfatória. / Occupants of artificially conditioned indoor spaces are continuously and lengthily exposed to environmental conditions mostly adverse to their activities performance and health maintenance. The purpose of this research was to evaluate some indoor air quality and thermal comfort parameters of an artificially conditioned building, and relate them to the employment of underfloor air conditioning system in spaces that differ from open-plan office spaces. Considering the studied building presents different activities on each of its floors it was necessary to choose two of them, one characterized by classrooms layout and the other by a semi open-plan office layout. The on-site data collection took place in three different steps. Step one was distinguished by three six-month cycles of air temperature, relative humidity and air velocity measurements, and fungi, particulate matter and carbon dioxide concentrations. The second step consisted of a four-day single campaign of measurements, when air temperature and relative humidity profiles were carried out, air velocity was quantified in complaining areas, and the Predicted Mean Vote (PMV) and Predicted Percentage of Dissatisfied (PPD) thermal comfort indexes were determined. During the third and last step, indoor environmental quality questionnaire surveys were distributed to the occupants of both studied floors. Data analysis and assessment originated from the cycles identified exceeding fungi and carbon dioxide concentrations. Temperature profiles indicated their prevalence below the recommended range. PMV and PPD indexes determination pointed to a scenery of best thermal environmental conditions for the researched spaces, with an operative temperature of 24 Celsius degrees. The results of the questionnaire surveys supported the air temperature measurements, showing supremacy of cold related thermal sensations among the occupants, especially those of female gender. It was evident that the thermal comfort of the studied environments is a disturbing factor for the activities practiced on both floors. There was a great number of occupants reporting Sick Building Syndrome (SBS) typical symptoms, what suggested actions related to indoor environmental quality should be taken in order to provide the desired health, welfare and productivity for the building occupants. It was conclusive that the operation and maintenance of underfloor air conditioned systems in indoor environments unlike open-plan offices are more complex and therefore make it harder to reach an acceptable indoor environmental quality.
918

Análise espaçotemporal da qualidade do ar em vias urbanas por meio de redes de sensores com nós embarcados em ônibus coletivos. / Spacio-temporal analysis from air quality in urbvan streets by wireless sensor networks with node hosted on public transport buses.

Santos, Alessandro Santiago dos 08 December 2017 (has links)
Os veículos que compõem o tráfego urbano são considerados como o principal agente causador de poluição afetando diretamente a qualidade do ar nas cidades, sendo um desafio ter mecanismos de monitoramento que possibilitem uma visão geral das condições ambientais. Para proporcionar uma visão abrangente seria necessário um grande número de estações fixas de monitoramento da qualidade do ar, além de um incremento constante para acompanhar o crescimento da cidade. Neste cenário, surge a oportunidade de instrumentação de ônibus coletivo com sensores que medem a qualidade do ar durante seu trajeto, assim aproveitando as características de mobilidade do transporte público, o qual transita em áreas povoadas, com postura dinâmica de crescimento, adaptando-se de forma coerente à mutabilidade populacional e geográfica da cidade. A presente tese apresenta novas formas de realizar análises espaçotemporais da qualidade do ar de regiões urbanas. Os modelos cartográficos criados permitem analisar regiões mapeadas usando perspectivas espaciais e temporais com informações obtidas de kits sensores móveis, para análises a cada 100 metros, promovendo uma resolução maior que os modelos tradicionais de monitoramento (escala quilométrica), os quais ainda não oferecem esta possibilidade. Esta maior resolução permite uma nova perspectiva de análises de microrregiões e, desta forma, permite que os especialista ou gestores urbanos possam entender melhor as situações, ao utilizarem as ferramentas e recursos apresentados pela presente tese. Para atingir os objetivos optou-se pela criação e validação de um kit sensor para ser hospedado em ônibus coletivo, o qual foi validado e testado, quanto à sua eficiência de medição. Este kit foi integrado a uma plataforma computacional construída para extrair e processar informações com algoritmos matemáticos. Todos os componentes da plataforma foram legitimados com experimentos que confirmaram as hipóteses inicialmente formuladas para validação. E por fim, mapeamentos com mais de 70 mil pontos foram utilizados na criação de modelos espaçotemporais para realização de estudo de caso de regiões da cidade de São Paulo, os quais demostraram os usos potenciais das proposições desta tese. / The vehicles in urban traffic are considered as the main cause of urban pollution with a direct impact on air quality, being a challenge to have monitoring tools that enable an overview of the environmental conditions influenced by vehicle emissions. One option is to instrument the entire city with low-cost fixed sensors to collect environmental data; however, to provide a comprehensive view would require a large number of sensors, and a constant increase to follow the growth of the city. In this scenario, arises the opportunity for urban bus instrumentation with sensors that measure the environmental pollution, to take advantage of the mobility characteristics of public transport, which moves in populated areas, with dynamic attitude of growth, adapting in a coherent way to population and geographic variability of the city. This PhD Thesis proposes the monitoring of air quality inside urban roads by Wireless Sensor Networks (WSN), hosted on city buses. Thus, new ways of performing spatiotemporal analyzes of the air quality of urban regions are possible with the cartographic models created by this thesis. These allow to analyze mapped regions using spatial and temporal perspectives with information obtained from mobile sensor kits, for analyzes every 100 meters, promoting a resolution higher than the traditional monitoring models (kilometer scale), which still do not offer this possibility. This higher resolution allows a new perspective of analyzes of micro regions and, in this way, allows specialists or urban managers to have a better understanding of the urban scenario. Sensor kits are created to be hosted by bus, which has been validated and tested for its efficiency in measurement. This was integrated into a computational platform built to extract and process information with mathematical algorithms. All the components of the platform were validated with experiments that confirmed the hypotheses originally formulated for validation. Finally, mappings with more than 70,000 points were used in the creation of spatiotemporal models for the study of the case of regions of the city of São Paulo, which denoted the potentials constructed by this thesis.
919

En jämförande studie av luftkvalitet ombord fartyget M/S Aurora af Helsingborg före och efter konvertering från dieselelektrisk drift till batteridrift / A comparison study for indoor air quality onboard the vessel M/S Aurora af Helsingborg before and after conversion from diesel-electric operation to battery operation

Heimdahl, Alva, Lilja, Emil January 2019 (has links)
Syftet med arbetet har varit att undersöka hur arbetsmiljön och innemiljön med avseende på luftkvalitet har förändrats ombord fartyget M/S Aurora af Helsingborg efter konvertering från dieselelektrisk- till batteridrift. Resultatet har sedan jämförts med Arbetsmiljöverkets hygieniska gränsvärden, WHOs riktlinjer och tidigare mätning på Aurora som utfördes 2014, innan konverteringen till batteridrift. Då bestod framdrivningen av fyra Wärtsilä-Vasa 6R32E dieselmotorer som körde på miljödiesel. Under sju dagar i mars 2019, från nionde till sextonde, har mätdata samlats in på fartyget Aurora genom olika passiva provtagare för: Polycykliska aromatiska kolväten (PAH), lättflyktiga organiska ämnen (TVOC), temperatur, relativ luftfuktighet, partiklar, SO2 och NO2. Resultaten av mätvärdena visade att det är bra Luftkvalitet ombord på fartyget och att innemiljön blivit bättre sedan konverteringen. Alla uppmätta halter låg långt under de hygieniska gränsvärdena som Arbetsmiljöverket tagit fram. Nivåerna låg även under riktlinjerna bortsett från TVOC i separatorrummet där halterna är betydligt högre än riktvärdet. Arbetsuppgifterna ombord Aurora har förändrats till det bättre sedan konverteringen med bland annat mindre hantering av oljeprodukter. / The purpose of this study is to examine how the work environment and indoor air quality has changed onboard M/S Aurora af Helsingborg after the conversion from diesel electric to battery. The results have been compared to Swedish Work Environment Authority (Arbetsmiljöverket) hygienic exposure limits, World Health Organizations (WHO) guidelines and previous measurements from 2014 done on Aurora before the conversion to battery drive. At that time Aurora was propelled by four Wärtsilä-Vasa 6R32E diesel engines running on environmental diesel. During seven days in March from 9th to 16th 2019, data was collected on the vessel Aurora by different types of passive samplers: Polycyclic aromatic hydrocarbons (PAH), benzo(a)pyrene, total volatile organic substances (TVOC), benzene, temperature, relative humidity, particulate matter (PM), SO2, NO2. The result from the data collected showed that the indoor air quality onboard and the inside environment has improved after the conversion. All measured data were much lower than the hygienic limit values that Swedish Work Environment Authority has set. The values of the data were also lower than recommendations except from TVOC in purifier room. The duties on board Aurora has changed for the better since the conversion, including less management of oil products.
920

Análise espaçotemporal da qualidade do ar em vias urbanas por meio de redes de sensores com nós embarcados em ônibus coletivos. / Spacio-temporal analysis from air quality in urbvan streets by wireless sensor networks with node hosted on public transport buses.

Alessandro Santiago dos Santos 08 December 2017 (has links)
Os veículos que compõem o tráfego urbano são considerados como o principal agente causador de poluição afetando diretamente a qualidade do ar nas cidades, sendo um desafio ter mecanismos de monitoramento que possibilitem uma visão geral das condições ambientais. Para proporcionar uma visão abrangente seria necessário um grande número de estações fixas de monitoramento da qualidade do ar, além de um incremento constante para acompanhar o crescimento da cidade. Neste cenário, surge a oportunidade de instrumentação de ônibus coletivo com sensores que medem a qualidade do ar durante seu trajeto, assim aproveitando as características de mobilidade do transporte público, o qual transita em áreas povoadas, com postura dinâmica de crescimento, adaptando-se de forma coerente à mutabilidade populacional e geográfica da cidade. A presente tese apresenta novas formas de realizar análises espaçotemporais da qualidade do ar de regiões urbanas. Os modelos cartográficos criados permitem analisar regiões mapeadas usando perspectivas espaciais e temporais com informações obtidas de kits sensores móveis, para análises a cada 100 metros, promovendo uma resolução maior que os modelos tradicionais de monitoramento (escala quilométrica), os quais ainda não oferecem esta possibilidade. Esta maior resolução permite uma nova perspectiva de análises de microrregiões e, desta forma, permite que os especialista ou gestores urbanos possam entender melhor as situações, ao utilizarem as ferramentas e recursos apresentados pela presente tese. Para atingir os objetivos optou-se pela criação e validação de um kit sensor para ser hospedado em ônibus coletivo, o qual foi validado e testado, quanto à sua eficiência de medição. Este kit foi integrado a uma plataforma computacional construída para extrair e processar informações com algoritmos matemáticos. Todos os componentes da plataforma foram legitimados com experimentos que confirmaram as hipóteses inicialmente formuladas para validação. E por fim, mapeamentos com mais de 70 mil pontos foram utilizados na criação de modelos espaçotemporais para realização de estudo de caso de regiões da cidade de São Paulo, os quais demostraram os usos potenciais das proposições desta tese. / The vehicles in urban traffic are considered as the main cause of urban pollution with a direct impact on air quality, being a challenge to have monitoring tools that enable an overview of the environmental conditions influenced by vehicle emissions. One option is to instrument the entire city with low-cost fixed sensors to collect environmental data; however, to provide a comprehensive view would require a large number of sensors, and a constant increase to follow the growth of the city. In this scenario, arises the opportunity for urban bus instrumentation with sensors that measure the environmental pollution, to take advantage of the mobility characteristics of public transport, which moves in populated areas, with dynamic attitude of growth, adapting in a coherent way to population and geographic variability of the city. This PhD Thesis proposes the monitoring of air quality inside urban roads by Wireless Sensor Networks (WSN), hosted on city buses. Thus, new ways of performing spatiotemporal analyzes of the air quality of urban regions are possible with the cartographic models created by this thesis. These allow to analyze mapped regions using spatial and temporal perspectives with information obtained from mobile sensor kits, for analyzes every 100 meters, promoting a resolution higher than the traditional monitoring models (kilometer scale), which still do not offer this possibility. This higher resolution allows a new perspective of analyzes of micro regions and, in this way, allows specialists or urban managers to have a better understanding of the urban scenario. Sensor kits are created to be hosted by bus, which has been validated and tested for its efficiency in measurement. This was integrated into a computational platform built to extract and process information with mathematical algorithms. All the components of the platform were validated with experiments that confirmed the hypotheses originally formulated for validation. Finally, mappings with more than 70,000 points were used in the creation of spatiotemporal models for the study of the case of regions of the city of São Paulo, which denoted the potentials constructed by this thesis.

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